Edge-setting machine



Feb. 26,1929. 1,703,194

- E. JERRAM ET AL EDGE SETTING MACHINE v Filed June 9 1920 e sheets-sheet 1 Feb. 26, 1929. 1,703,194

A. E. JERRAM ET AL EDGE SETTING MACHINE Filed June 19' 1920 6 Sheets-Sheet 2 66\ I02 I 5 v s J J: (3 332 534. h I 1' .I I 1 x\\"-" I //\)VENTUF 8 7 M2 M Fig. 6.

Feb. 26, 1 929. 1,703,194

A. E. JERRAM ET AL EDGE SETTING MACHINE Filed June 19 1920 6 aheees -sheet 5 0 .2. 1 2 0 pg; n: Q 1: 0'6 I 5. 5. ,42 2,

'' l l'j kL Feb. 26, 1929. 1,703,194

A. E. JERRAM ET AL EDGE SETTING MACHINE Filed June 19. 1920 s Sheets-Sheet 4 v N V I A. E. JERRAM ET AL EDGE SETTING MACHINE Feb. 26; 1929. 1,703,194

Filed {une l9 v 2 I 6 Sheets-Sheet .5

7 1 D mini mg 1 M mllllllu' Feb. 26, 1929. 1,703,194

A. E. JERRAM ETAL EDGE SETTING MACHINE Filed June 19 ESheeta-Sheet 6 Patented Feb. 26, H

fu i ojs ATEs- PATENTL OFFICE.

' RTHUR ERNEST maxim AND FRANK nYcaor'r KEALL, or LEICESTER, ENGLAND, 'ASSIGNOBS 'ro UNITED snon MACHINEBY coarom'rxom'or PATEBSON, NEW

JERSEY, A CORPORATION or EW JERSEY. v

EDGE-SETTING MACHINE. g I Application filed June-19,1920, Serial'No. 390,146, and in Great Britain July 16, 1919.

This invention relates to control mechamain work-tool-controlcpiston getsinto a 55 nism, and more especially to automatic 'mastate of oscillation,-due to minute anomalous chinery wherein the relative movement of impulsesdeliveredto the feelers by roughness v the work and a tool is controlled automation the pattern surface, vibration, and other cally. as by hydraulic valve mechanism. causes. The invention therefore provides also 4 The invention will be disclosed as" em-: for the elimination :of hunting by insuring '6 bodied in an edge setting machine of the that a'substantial feeler movement shall be type disclosed inUnited States Letters Patnecessary to throw the main correcting pis ent No. 1,07 8,684, granted on the applicaton from one species of its movement to the 10. tion of Keall, Gouldbourn and J erram, but other; This creates a certain sluggishness of is not to be considered as limited in its adthe control mechanism, but does not make it 65 I 'plication to machines of this type since vainsensitive, in the sense of being unreliable. rious features of the invention are capable The parts moved by the feelers are so small of other uses. that the lightest impulse will move them, but Machines of the general type above reit is necessary to move them a'substantialferred to comprise a tool and a work supdistance before the machine will respond. 70

port arranged for relative movement (pref- This is assisted by providing a member erably automatic) to cause thepoint of opermovable to effect desired corrections, but ofation of the tool to be transferred alon the fering a discontinuously variable resistance work, and a controlling mechanism which or tendency to movement at a certain posiacts during the transfer to control or correct tion, so that hunting about this position is 75 automatically as, for example, by feelers, the avoided. In the machine shown this is acrelative positions of the tool and work in accomplished by imposing adiscontinuously accordance with changes in their relations varying resistance or stress upon a member due to the pro ress of the operation; The movable to effect the desired correction. The

controlling. mechanism may comprise gages, feeler motion necessary to take up the dlSCODs-r 80 feelers, or other contact members, and in the tinuity insures that mere adventitious movemachine shown, is operated by feelers bearments of the feelers will not influence the ing directly upon the work, but it may cocorrecting mechanism. I

operate with any form or contour or pat- Afeature of the invention consists in a tern surface having a desired definite relamember movable to effect corrective changes 5 tion to the work. I in the relation between the work and the tool In the machine shown in the above menand means for moving the member by means -tioned patent this correcting mechanism of unbalanced opposing stresses, one of said comprises a hydraulic piston, the movement stresses being discontinuously variable when of which effects the corrective movements dethe member is at a certain position, so that 99 sired, and a main valve controllin the pis-- hunting about this position is avoided. In ton, the main valve being operategdirectly the machine shown the member-is a piston by a work or pattern contact control. Onv the valve and the discontinuously varying stress 40 other hand, the illustrated machine provides is-supplied by springs of varying strengths,

a control-operated relay *valve for operating arranged to come into operation successively. 95 the main valve with the advantage that the .These and other features of the invention mainvalve can be. made as rugged and heavy comprising certain. combinations and artin constructionas desired, since it is no rangements of arts will be understood from longer necessary to move it by the minute the following riiascription of a preferred eincontrol impulses, and the relay valve can bodiment thereof selected for purposes of 20o be made light and diminutive and therefore illustration and shown in the accompanying exceedingly sensitivejtosmall variations in drawings in whicht I control-imposed stress. i Fig. 1 is a front elevation of the machine The great sensitiveness produced by this with a part of the frame broken away to relay valve mechanism brings with it a new show the internal construction. 10s but natural difiiculty which is found to re- Fig.2 is a plan view of the machine shown quire correction. The mechanism is so sensiin Fig. 1 wit the upper part removed. 4 tive that it hunts continually; thatis', the Fig. 3 is a side view of a P01131011 of the machine shown in Fig. 1 drawn to a larger scale, with certain parts in section.

Fig. 4 is a vertical section showing in detail the tool carrying head.

Fig. 5 is a plan" partly in section of the partsshown in Fig. 4.

Fig. 6 is a front elevation showing certain details of the feeler mechanism.

Figs. 7, 8 and 9 show in three positions the valves which control the supply of fluid to the correcting hydraulic cylinders, the casing being tipped over from its normal vertical position in the machine, with the parts at the right of these figures at the lower end.

Fig. 10 is a perspective of the tool carrying head.

Fig. 11 shows the mechanism for bringing the jack to normal work inserting position, and

Fig. 12 is a similar view of a modified form of valve.

Only enough of the machine is described in detail to enable the invention to be understood. For a fuller description of parts not material to the present invention, reference is to be made to Patent N 0. 1,078,684, above mentioned.

In this specification it is to be understood that by the path of relative traverse of the tool is meant that path in which, during the relative motion of the tool and work, the tool is in active operation on the work; and it is contemplated that this path may be shorter than the extent of relative movement of the tool and work, since these members may be sov controlled as to move clear of each other before the relative motion of tool and work has ceased.

The machine comprises a jack or work support upon which the boot or shoe is securely held and an edge setting tool that has rapid vibratory movements of small amplitude imparted to it to burnish the sole edge of the shoe with which it is maintained in engagement.

The jack comprises a frame 2 of a laterally disposed U shape on the lower arm of which is a dove-tailed slideway 4 that supports an adjustable block 6 for engaging and positioning the tread face of the sole of the shoe; this block may be adjusted longitudinally of the shoe along the slideway-and be retained in its adjusted position by any suitable means such as a spring plunger 8 so located in the frame as to engage suitably .shaped recesses in the block 6. Toward the bend of the U- shaped frame there is an adjustable, vertically-disposed rest 10 for the tread face of the heel of the shoe.

A U-shaped clamp 12 adapted to embrace the counter portion of the shoe so as to position it centrally in the jackv is adjustably mounted in the bend of the frame.

The shoe is held upon the jack by a pendentclamp member 14 carried in the upper arm of the frame and operated by the handle 20 so as to engage the shoe and hold it firmly in the jack. A more detailed description of this clamp is not necessary to the disclosure of the present invention but it will be found, if desired, in Patent No. 1,078,684, above referred to.

The jack and tool are moved relatively by one end of a frame 44 of which the other end is pivotally carried at 46 (see Fig. 2) upon a second frame 48 that swings about a vertical spindle 50 supported in the machine frame. The two frames 44 and 48 in their mean position are disposed approximately at right angles to each other so as to permit horizontal movements of the jack in any direction.

A lobed cam 52 fixed to the lower end of the spindle 42 has a cam groove formed in it which engages two rollers 54, 54 which are supported in a manner hereinafter described. The cam and rollers so guide the ack during its movement that the sole edge of the shoe on the jack moves past the tool in a path agreeing approximately in shape with the contour of the sole edge, or in a path that is the mean of a variety of contours of shoe soles; the relative traverse of the tool and sole edge being brought into exact agreement with the contour of the shoe under operation by the horizontal and vertical movements which are imparted to the jack and tool respectively by the feeler mechanism.

The mechanism-for driving the jack 2comprises a slide 56 that is mounted to reciprocate in guideways 58 and'60 attached to or formed upon the machine frame. The slide 56 is coupled by a piston rod 62 to the piston 64 of a hydraulic cylinder 66 secured to the machine. Motion is transmitted from the slide 56 to thejack by means of twochains or other slmilar flexible members 68 and 70.

The chain 68 is secured to the slide 56 at one end and after passing around pulleys 72, 74 and 76 is attached at its other end at 78 to the cam 52; and the chain 70 also secured to the slide 56, passes around pulleys 80, 82, 84, 86, 88, as shown in Figs. 2 and 3, and is joined to the cam at 90. To increase the motion derived from the slide 56 the pulleys 74 and 8.2 are mounted upon the slide while the remaining pulleys, except 84, are. carried upon the machine frame. The pulley 84 is carried upon a lever 92 pivoted to the machine frame and is acted upon by a spring pressed rod 94 to keep the chains 68 and 70 under the necessary tension. If desired, the chains instead of being attached to the cam may be secured to a pulley of corresponding formation.

By the connections above described, the jack is oscillated from side to side by the reciprocation of the slide 56 and the direction of motion of the slide is reversed automatically by a mechanism not necessary to be described here, a full description of which will be found in Patent No. 1,078,684, already referred to-. This mechanism operates the valve 102 that controls the supply of fluid to both sides of the piston 64 in the hydraulic cylinder 66 before mentioned.

The point of operation of the tool is transferred along the sole edge of the shoe, fro-1n the shank on one side of. the sole, around the toe portion, to the shank on the other side of the sole; the direction of motion of the jack being reversed when the tool reaches ,the shank.

The edge setting tool 200 (Fig. 4) has an acting face 202 to engage the sole edge and is provided with a lip to engage the underside of the sole edge. The upper side of the sole edge preferably is engaged by a stitch wlnlaeling disk 204 that is pivoted upon the too The tool is movably mounted in a holder 206 so that it may turn freely about the center 207 in a vertical plane transverse to the end of the shoe. The shank 208 of the holder 206 is slidingly keyed in a T-shaped piece 210 (Figs. 4 and 5) having a vertically extending stem 211 fulcrumed in a bushing 213 in an extension 212 from a sleeve 214 that is rotatably mounted at 215 in a bearing frame 216 supported by pivots 218 which couple it to two pairs of twin levers 220, 222. The twin levers 220 are pivoted upon a frame lever 224 pivoted at 226 (Fig. 1) upon the machine frame. The twin levers 222 are connected to the frame lever 224 by a bell crank lever 228 pivoted at 230 to the frame lever 224. The other end of the bell crank lever 228 is coupled to a projection from the machine frame by means of an anchor link 232. By this construction the tool holder 206 can be vibrated laterally about the fulcrum 211 of the T-sha-ped piece 210; the sleeve 214 and tool holder 206 can be angled about the common axis of the shank 208 and of the sleeve 214; while the sleeve 214, tool holder 206 z and bearing frame 216 during their lateral ly about the axis of the stem 211 by connections from a shaft 234. This shaft may be oscillated by any suitable mechanism but preferably by a mechanism of the type described in the specification of U. S. Patent No. 1,035,445, granted Aug. 13,1912. This mechanism is indicated at 236, Fig. 1, and is not herein described as it, in itself, forms no part of the present invention. The mechanism may be conveniently operated from the pulley 2348 (Figs. 1 and 3). The shaft 234 is connected with the tool holder 206 by a universalv coupling comprising a sleeve 238 (Figs. 4, 5 and 10) open at the top, as at 239 (Fig. 5) to admit the member 210 (the ends of the sleeve being pivoted upon the shank 208 outside the member 210) and a fork 240 that is secured to the shaft 234'and is pivotally" connected with the sleeve 238 by a pin 241 disposed at right angles to the shank of the tool holder. The member 238 constitutes the cross-shaped member of the universal joint between the shaft 234 and the stem 211.

Backward thrust of the tool owing to its pressure upon the work is transmitted to the bearing frame 216 by a thrust rod 242 seated atone end against a set screw 244 screwed into the frame 216, its other end engaging the bottom of a recess in the shank 208 of the tool holder 206, the point of engagement being located at a point in the axis of the T-shaped piece 210.

The tool 200 is pressed against the sole edge of the shoe by means of a spring 246 (Figs. 1 and3) and by the co-operation of this spring with the cam 52 on the lower end of the spindle 42 of the jack 2vthe point of operation of the tool is caused to travel along the sole edge during the movement of the jack. But it is necessary during the move ment of the jack that there be angular movement in a horizontal plane between the jack and the tool to maintain always the acting face of the tool in proper engagement with the sole edge at every part of the contour thereof. Further, it is necessary also that the jack and tool be turned relatively about an axis that is normal-to the acting face 202 of the tool owing to the factthat all parts of the sole do not lie in. the same plane. These movements of adjustment between the jack and the tool are effected autdina; ally by the correcting devices hereinafter dc ribed. I

The correcting device for an i he Tack in a horizontal plane ,inrelation. ,the tool comprises a hydraulic cylinder 248"(l i g f 2), the piston rod of which is connected by a link to a jack correcting lever 250 pivoted at 252 to the machine frame. This lever supports the two rollers 54, 54 hereinbefore referred to as engaging the groove in the cam 52 on the.

lower end ofthe jack spindle. The valve 254, (Fig. 1) of the hydraulic cylinder is con-' trolled by two feelers 256, 258 (Figs. 5 and V 6) which, under the action of suitable springs,

bear upon the sole edge, one on each side of the-ed e setting tool 200. The feeler 256" is couple to one end of a lever 260 pivoted upon an extension from the sleeve. 214 and the feeler 258 is coupled to a lever 262 also pi oted upon the sleeve 214. The lower'ends of the levers 260,262 are'c'onnected by a cross bar 264 (see Fig. 6) which constitutes one element of a universal 'oint connected to the upper end,

' of a shaft 266 aving at its lower end a similar and transmitting motion, by partial rotation- 4 of the shaft 266, to the valve 254. The valve being thus actuated causes the piston of the cylinder 248 to be set. in motion so that the jack correcting lever 250 is turned upon its pivot 252. The ack 2 being connected to the lever 250 by therollers 54, 54 and the cam 52 I will-alsobe swung about the pivot 252 of the lever 250 as a center until the sole edge of the shoe on the jack is returned by such movement to the position in which the tool bears evenly upon'it, by which time the feelers motion of the piston and of the partscon- 256, 258 will likewise be restored by the movement of the sole edge to theirinitial position and they will close the valve 254 and stop the nected therewith. Y

. The correcting device'that eii'ects a"re1ative turning movement of jack and toolabout an axis that is normal to the acting face of the tool comprises a hydraulic cylinder 27 0,

(Fig. 3) the piston of which'is connected by a thrust r0d'27 2 (F igs.'3'and 10) with an extension 274 from a collar that is secured to the projection 212 from the sleeve 214. .A spring 276 (Fig. 4) connects the sleeve 214 and the bearing frame 216 and opposes the thrust ofthe rod 272. The valve 278 (Fig. 1) that re gnlates the admission of fluid to the cylinder 270, is controlled by two feelers 280, 282 (Fig.

5) that bear upon the tread face of the sole of the shoe immediately adjacent to the sole" edge. Thesefeelers are formed as springsus. tamed levers pivoted upon extensions from the sleeve214, the free ends of the leversbeing coupled by a cross bar 284 (Fig. 4) connected by a universal coupling and a shaft 286, with 66 the rotary valve stem of the cylinder 270.

The action-of this correcting device is similar to that first mentioned, that is to say the.

' feelers 280, 282 being displaced relatively by changes in the contour o sole engaged by them, angle the crossbar 284 and turn the valve 27 8 so that the latter is the portion of the actuated either to cause thejpiston of the c linder 27 0 to'be raised by the admission of uidor'to permit it to be depressed by the action of the spring 276 on the sleeve 214. The sleeve, tool holder and tool are thus turned about the axis of the shank ofthe latter to restore the sole edge andxtool to I their original relationship, namely one in which the plane of vibration of the tool coincides with that of the part of the sole edge engaged-by it. The angling of the-sleeve 214 causes the feelers 280, 282 bearing on the sole to be returned to their normal position,

thus again actuating the valve stem 278 and stopping the motion of the piston.

It may here be remarked that in order to permit movement of both' sets of feelers toward and away from-the valves controlled by them as the feelers follow the traverse of the tool, or as the tool carrying head is moved bodily toward and from the work, the shafts 266 and 286 preferablyare made telescopic and with pin and slot connections (see Figs. 1

-1 and 3) so that turning movements only, are transmitted to the valve. which imparts vibratory movement to""*th e tool is also made telescopic as shown in Fig. 1

to permit the movements of the before indicated. I

. To move the-tool into engagement with the tool .herein- The shaft 23*? sole edge or to remove it therefrom, a starting and stopping lever or controlling lever 290 is provided which is fixed upon a rockshaft 292 j'ournaled in the machine frame. The rockshaft 292 has upon it an arm 294 to which is pivotally linked a plunger 296 into which extends arod 298 free to turn within a bear-' .ing upon the frame lever. The spring 246,

the function of which is to keepthe tool 1 pressed againstxthe sole edge while the machine is in operation, surrounds the rod 298 and abuts at its lower end against a collar 300 supported by projectionsfrom a'nut 302 working on a screwed portion of the rod 298 and at its upper end against an abutment 304 limit the movement of the'rod in the abut-' ment 304 under the. influence of the spring 246. By this construction the tool can be pivoted on the lever 224. -A collar 306 secured -to the upper end of the rod 298 operates to moved yieldingly toward the sole edge and removed positively therefrom. Preferably the plunger 296 works ina dash pot 308 which cushions the movement of the lever 290 and arm 294 when the machine is thrown auto-- matically out of action.

- A pump 360 (Fig. 2) 'is. provided which supplies fluid, such as oil, under the requisite pressure to the hydraulic cylinders of the machine and there is anair pressure chamber 362 (Figs. 2 and 3) into which the fluid is pumped before passing to the hydraulic cylinders.

The valve. mechanism for operating the automatic correcting devices is contained in sion of spring which-rests against the piston and a casing 370 Fi s. 1, 7 8 and 9). This casing contains otli of the control valves for the mechanisms-i fer an ling the jack in a horizontal plane and rocl ring the. tool about a horizontal axis.- description of the for: mer of these mechanisms will suffice inasmuch as they are quite similar. The casing. 370

contains a cylindrical bore 372 (Fig. 8 en-- eter of the main body of the bore 372 so that it can rest against shoulder 375 at the place where: the bore changes size. Below the disk is a sp'ring392 substantially stiffer than the spring 386, one end of which rests against the disk and the other against the bottom of the casing 370. Thus the resistance offered to movement of the piston varies irregularly or discontinuously when the spring 386 has been-fully compressed and as the compres- 392 is commenced. A pin 394 is fixed in the piston 376 and serves to guide the springs and the disk, and extends outside the casing for a purpose to be described below. One side of the casing has two ports 396, 398 from which pipes lead to the ends of the cylinder 248 (Fig. 2) to operate the piston therein. These ports are spaced to co-act with the valve portions 381, 383. The other side of the casing has three ports 400, 402, 404 connected to the pump 360. When the piston 376 is in the position shown in Fig. 7, oil from the pump 360 entersthe port 402, passes around the reduced portion 380 and into the port 396, operating the piston in the cylinder 248. The oil on the other side of the piston in through the port 398 around the reduced portion 382 and out of the port 404 to the pump 360. 'When'the piston 37 6 is in the position shown in .F'g. 9, oil from the-pump enters through the port 402. passes around the reduced portion 380 and out of-the port 398 to operate the piston in the cylinder 248 in the other direction. The oil on the other side of the piston in the-cylinder exhausts through the port 396, passes around the reduced por tion 378 and returns to the pump through the port 400. When the main piston is in the position shown in Fig. 8, both the ports 396 and 398 are closed and the piston in the controlling cylinder 248 is held motionless.

The main valve piston 376 is operated by the following described mechanism. The shaft 266 passes into the casing 370 and carthe cylinder exhausts ries a lug 406 extending laterally from it. A small do 408 is pivoted at 410 upon the easing 370 111 positlon to be swung by contact of the lug 406 with one side of it as the shaft 266 is turned through a small are, Its other side engages a small lunger 412 slidin in a guide in the casing 3 0. reduced end of peculiar formation. The tip end is conical as shown at 414. Behind this conical end is a reduced cylindrical portion 416 which is joined to the main body of the plunger by another conical portion 418. The end is arranged to move in and out of a port 420 in the casing which extends between a chamber 422 leading to an outletpipe 424 and a recess or pressure chamber 426 formed in the top of the cylindrical bore 372/ A This plunger as a I very small inlet pipe 428.communicates with this recess, so that the pressure in the chamber depends on the extent of opening of the port 420.

Suppose the parts are in the Fig.7 position and that the feelers which control the shaft 266 are operated in such a way as to move the valve p1ston 37 6 from this extreme position.

The feelers will turn the shaft 266 in valve casing 370 so as to force the plunger 412 to the right in Fig. 7, thereby reducing the effective area of the aperture 420.. This causes the pressure in the chamber 426 to increase as the fluid is pumped in through the inlet pipe 428. \Vhen'the pressure increases sufliciently the piston 376 will 'move to the right compressing the spring386 until the end of the piston seats upon the disk 388. At this point the ports at 396 and 398 (Fig. 8) will be closed, the cylindrical portion 416 will just be entering the port' 420, and the 3 control piston in the eyhnder 248 will be locked. It will not yet have begun any re? verse movement, but if it was moving at the time the plunger 412 began to move, its move-. ;ment in that direction will gradually have stopped. Further movement of the piston 376 cannot occur until the pressure in the chamber 426 has increased abruptly a substantial amount equivalent to the (substandifference in the pressures exerted by tial) The major part of the springs 386' and 392.

this increase in pressure will occur after the cylindrical portion 416 of the plunger has passed into the port 420. The purpose of this cylindrical portion is to necessitate. an appreciable movement of the feelers in raising the pressure in the chamber 426 to the required degree so pressure chamber is an increasing but discontinuous function of the position of the piston, reckoned from one extreme to the other of the movement of the piston. The pressure having reached the required point, the disk 388 moves back against the spring 392, compressing it until the parts reach the position shown in Fig. 9 at which time the ports at 396 and 398 will have been uncovered that the pressure in the and the oil will pass through them in the direction opposite to that in which it was passing at the beginning of the described cycle, and the correcting movement initiated by the movement of thefeelers will take place.

The behavior of the apparatus is quite similar in moving in the opposite direction. As the pressure in the chamber 426 drops due to the action of the feelers in allowing the valve 412 to open, the piston 376 moves to the left in Fig. 9 until the spring 392 has seated the disk 388 on the shoulder 375, and the pressure is then permitted to drop a substantial degree after a substantial movement of the plunger 412, before the piston 376 begins to move again. r

The mechanism described, comprising the two springs and the cylindrical portion of the plunger 416 will thus cause a certain slightsluggishness in response to the feeler movement, but will entirely prevent hunting inasmuch as a substantial difference in pressure in the chamber 426, which means a substantial movement of the feelers, is necessary in order to change the control from one phase to the other. The plunger 412 and its operating parts can be made very small and light I in weight since the aperture 420 need not be at all large and therefore the response of the plunger to the reaction between the work and i the feelers is practically instantaneous. At

the same time, the main valve structure, comprising the piston 376 and its related parts, can be made as heavy and rugged as is found necessary, instead of being governed in construction by the force exertable by the feelers which ultimately control it, as would be the case if the'feelers operated upon it directly. The force which operates the main valve piston 376 is the pressure of springs acting to lift the piston and the pressure in the chamber 426 and the adjoining part of the bore 372 above the piston acting to depress the piston toward the right in Figs. 7, 8 and 9. This pressure may be varied by the additional or subtractional flow of asmall quantity of fluid and this flow may take place at any desired part of the chamber. Therefore the plunger 412 may be located as conveniently as desired to the feelers while the main valve piston may be located elsewhere in the machine where it will be out of the way. The

. chamber 426, of'course, may be reduced to a small pipe connecting the bore 372 with the aperture 420, all that is necessary being ameans of transmitting hydrostatic pressure to the piston 376. I

v The mechanism for maintaining the jack in convenient position for, the insertion of newwork will now be described.

On the jack correcting lever 250 (Fig. 2)

is fast an upstanding arm 430 (Fig. 11) piv- ,oted to which ona horizontal pivot 432 is a second arm 434 having a cam 436 on its upper surface immediately below the lower end of the pin 394 (see also Figs. 7 and 8) The end of this arm 434 rests upon and is supported by one end of a lever 438 pivoted between its ends on a horizontal pivot 440 at one end of a vertically disposed'bell crank 442 pivoted to the frame of the machine at 444 and the remainin end of which is connected by a third horizontal pivot 446 to one end of a rod 448 the opposite end of which is threaded into a nut 450 held from endwise movement in the frame of the machine and provided with an enlarged knurled head easily accessible to the operator. The other end of the lever 438 is bent downwardly at 452 and held in contact with the frame of the machine by a tension spring 454.

A projection 456 from the lever 438 on the same side of its fulcrum as the downwardly bent end 452 is in the path of a push rod 458 pivotally connected to a crank arm 460 on the starting shaft 292 to rise as the starting lever finishes its travel in the starting operation and move the lever 438 to allow the arm 434 and its cam surface 436 to fall, thereby releasing the piston valve to the control of the relay valve and feelers.

-Movement of the jack in that direction in which leakage through the valve system tends to move the jack when the tool head is in inoperative. position will be accompanied by corresponding movement of the jack correcting lever 250. The army 434 will move in company with it and the cam surface 436 (Fig. 7 is so formed that when moving in such a direction it will act on the pin 394 to move the piston member 376 in a direction to cause movement of the jack in the sense opposite to that in which leakage tends to move it. Consequently these opposing influences establish a balance determining a definite position of the jack notwithstanding leakage, which position may be readily varied by rotation of the knurled head 450 aforementioned which moves the bell crank about its fulcrum and raises or lowers the fulerrnn 440 of the lever 438 which it supports and the downwardly bent end 452 of which is definitely positioned by the frame.

The mechanism above described is entirely automatic, independently of leakage in the piston valve, since a position of the jack-correcting' lever 250 other than'that for'which the machine is set will cause a movement of the pin 394 in a direction to move the jack correcting lever 250 back to the normal position. It may, however, be sometimes regarded as desirable to set the valve to leak 12. The piston 376 would then be shifted to the right in Fig. 8, by the dropping ot the pin 394 along the cam 436 until the port 398 barely opened as in Fig. 9 so that the tendency to leak would just be balanced.

The automatic jack control mechanism above described is not claimed herein since it constitutes the subject-matter of Patent No. 1,472,071, granted October 30, 1923, upon the application of Frank B. Keall. a

Having described our invention, what we claim as new and desire to secure by Letters Patent of the United States is A 1. A fluid control mechanism comprising a cylinder having ports, a piston valve arranged to slide in said cylinder to control said ports, a pressure chamber in communication with one end of the cylinder to provide pressure for moving the piston valve, a spring to oppose such movement of the piston, an inlet port for said chamber, an outlet port, a slidable needle valve for controlling said outlet port and adjusting the pressure in the chamher, said needle valve comprising a plunger having a portion of substantially uniform cross-section movable out of and into said outlet port and another portion of rapidly increasing cross-section arranged to be moved into said outlet port thereby to decrease its efl'ective opening more than can be accomplished by the portion of uniform cross-section, and automatically operated means for sliding said needle valve to-the desired position.

movement of the piston, an inlet port for said chamber, a cylindrical outlet port,.and a needle valve for controlling said outlet port and adjusting the pressure in the chamber, comprising a plunger having a conical portion and a cylindrical portion movable out of and into said port, said portions being arranged to enter said port successively, where-,

by after the plunger has moved a certain dis fame to cause the cylindrical portion to enter the port and the pressure'in the/chamber has risen correspondingly, a substantial further movement of the plunger will cause no substantial further increase in pressure.

3. A fluid control mechanism comprising a cylinder, a "piston control valve arranged v to slidein said cylinder, a pressure chamber in communication with one end of the cylinder to provide pressure for moving the pis ton, a resisting mechanism to oppose such movement of the piston, an inlet port for said chamber. a cylindricalbutlet port,-and are lay needle valve for controlling said outlet ort and adjusting the pressure in the chamlier, comprising a plunger having a conical portion, an intermediate cylindrical portion, and a second conical portion, said portions being arranged in order along it to enter said port successively, whereby after the plunger has moved a. certain distance and the pressure in the chamber has risen correspondingly, a substantial further movement of the plunger will cause no substantial further increase in pressure, and a still further movement of the plunger will cause the pressure to continue increasing.

4. A fluid control mechanism comprising a cylinder having ports, a piston control valve arranged to slide in said cylinder to control said ports, a pressure chamber in commun1cation with one end of the'cylinder to provide pressure for moving the piston, a resisting mechanism to oppose such movement of the piston, said mechanism comprising a plurality of springs arranged in series to engage said piston, said springs having substantially, different characteristics, so that the force exerted by. the springs against the piston undergoes an abrupt change at an intermediate point in the range of movement of the piston, an inlet port for said chamber, an outlet port, and a needle valve for controlling saidoutlet port and adjusting the pressure in the chamher;

5. A fluid control mechanism comprising a cylinder having a central bore and enlarged end chambers, a piston valve arranged to slide in said central bore, one of said chambers constituting a pressure chamber in communication with one end of the cylinder, a needle valve for controlling the pressure in the pressure chamber, a spring having one end resting against the piston, a member having a dimension greater than thed-iameter of the cylinder against which the other end of the spring is seated. said member being positioned in said other end chamber, anda stiffer spring tending to force-said member against the end of the portion of the cylinder containing said central bore. I

6. A hydraulic valve mechanism comprising a piston valve having a socket in one end, a movable end wall for the piston cylinder,

a springseated in the socket and resting against the movable wall, said piston contacting firmly with said wall after-the spring has been compressed to the depth of the-socket. and a second spring having substantially different characteristics from said firstnamed spring tending to hold said wall in contact with the end ofthe cylinder.

In testimony whereof We have signedv our names to this specification.

. ARTHUR ERNEST JERRAM. FRANK BYCROFT'KEALL. 

